diff options
| author | Florian Fainelli <f.fainelli@gmail.com> | 2017-05-25 11:36:26 -0700 |
|---|---|---|
| committer | Richard Weinberger <richard@nod.at> | 2017-07-05 23:31:28 +0200 |
| commit | 0a987645672ebde7844a9c0732a5a25f3d4bb6c6 (patch) | |
| tree | 838f821a1b4a2ba33219fabac4913ad0a00180f4 /arch/x86/um | |
| parent | f44f1e7da7c8e3f4575d5d61c4df978496903fcc (diff) | |
um: Allow building and running on older hosts
Commit a78ff1112263 ("um: add extended processor state save/restore
support") and b6024b21fec8 ("um: extend fpstate to _xstate to support
YMM registers") forced the use of the x86 FP _xstate and
PTRACE_GETREGSET/SETREGSET. On older hosts, we would neither be able to
build UML nor run it anymore with these two commits applied because we
don't have definitions for struct _xstate nor these two ptrace requests.
We can determine at build time which fp context structure to check
against, just like we can keep using the old i387 fp save/restore if
PTRACE_GETRESET/SETREGSET are not defined.
Fixes: a78ff1112263 ("um: add extended processor state save/restore support")
Fixes: b6024b21fec8 ("um: extend fpstate to _xstate to support YMM registers")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Diffstat (limited to 'arch/x86/um')
| -rw-r--r-- | arch/x86/um/os-Linux/registers.c | 12 | ||||
| -rw-r--r-- | arch/x86/um/user-offsets.c | 4 |
2 files changed, 12 insertions, 4 deletions
diff --git a/arch/x86/um/os-Linux/registers.c b/arch/x86/um/os-Linux/registers.c index 00f54a91bb4b..28775f55bde2 100644 --- a/arch/x86/um/os-Linux/registers.c +++ b/arch/x86/um/os-Linux/registers.c @@ -26,6 +26,7 @@ int save_i387_registers(int pid, unsigned long *fp_regs) int save_fp_registers(int pid, unsigned long *fp_regs) { +#ifdef PTRACE_GETREGSET struct iovec iov; if (have_xstate_support) { @@ -34,9 +35,9 @@ int save_fp_registers(int pid, unsigned long *fp_regs) if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) < 0) return -errno; return 0; - } else { + } else +#endif return save_i387_registers(pid, fp_regs); - } } int restore_i387_registers(int pid, unsigned long *fp_regs) @@ -48,6 +49,7 @@ int restore_i387_registers(int pid, unsigned long *fp_regs) int restore_fp_registers(int pid, unsigned long *fp_regs) { +#ifdef PTRACE_SETREGSET struct iovec iov; if (have_xstate_support) { @@ -56,9 +58,9 @@ int restore_fp_registers(int pid, unsigned long *fp_regs) if (ptrace(PTRACE_SETREGSET, pid, NT_X86_XSTATE, &iov) < 0) return -errno; return 0; - } else { + } else +#endif return restore_i387_registers(pid, fp_regs); - } } #ifdef __i386__ @@ -122,6 +124,7 @@ int put_fp_registers(int pid, unsigned long *regs) void arch_init_registers(int pid) { +#ifdef PTRACE_GETREGSET struct _xstate fp_regs; struct iovec iov; @@ -129,6 +132,7 @@ void arch_init_registers(int pid) iov.iov_len = sizeof(struct _xstate); if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) == 0) have_xstate_support = 1; +#endif } #endif diff --git a/arch/x86/um/user-offsets.c b/arch/x86/um/user-offsets.c index cb3c22370cf5..8af0fb5d2780 100644 --- a/arch/x86/um/user-offsets.c +++ b/arch/x86/um/user-offsets.c @@ -50,7 +50,11 @@ void foo(void) DEFINE(HOST_GS, GS); DEFINE(HOST_ORIG_AX, ORIG_EAX); #else +#if defined(PTRACE_GETREGSET) && defined(PTRACE_SETREGSET) DEFINE(HOST_FP_SIZE, sizeof(struct _xstate) / sizeof(unsigned long)); +#else + DEFINE(HOST_FP_SIZE, sizeof(struct _fpstate) / sizeof(unsigned long)); +#endif DEFINE_LONGS(HOST_BX, RBX); DEFINE_LONGS(HOST_CX, RCX); DEFINE_LONGS(HOST_DI, RDI); |